Q What is the relative cost effectiveness of alternating pressure mattresses and alternating pressure overlays for preventing
pressure ulcers in hospital patients with limited mobility?

METHODS

Design:

randomised controlled trial (RCT).

Setting:

10 hospitals in the UK.

Patients:

1972 patients ⩾55 years of age (mean age 75 y, 64% women) admitted to vascular, orthopaedic, medical, or elderly care wards
in the previous 24 hours, with an expected hospital stay of ⩾7 days and limited activity and mobility (Braden scores of 1
or 2) or existing grade 2 pressure ulcer. Elective surgical patients were included if they were expected to have limited mobility
for ⩾3 days postoperatively. Exclusion criteria included ⩾ grade 3 pressure ulcer, planned admission to intensive care ward
after surgery, sleeping at night in a chair, and weight <45 kg or >140 kg.

Intervention:

alternating pressure overlay (n = 990) or alternating pressure mattress (n = 982) for duration of ward stay or until mobility
improved to a Braden score of 3 or 4.

Outcomes:

pressure ulcer free days (time to development of a new pressure ulcer ⩾ grade 2), length of hospital stay, hospital costs.